Schemachange

Added
- Added support for Oauth and external browser and Okta authentication methods.
- Added `--oauth-config` to accept values for oauth configuration.
Changed
- Inverted Program Call sequence and refactored all snowflake interactions into a Class. Class now persists connection accross all interactions and updates the snowflake query tag session variable as scripts are executed.
- Cleaned up argument passing and other repetitive code using dictionary and set comparisons for easy maintenance. (Converted variable names to a consistent snake_case from a mix of kebab-case and snake_case)
- Fixed change history table processing to allow mixed case names when '"' are used in the name.
- Moved most error, log and warning messages and query strings to global or class variables.
- Updated readme to cover new authentication methods

Changed
- Updated `snowflake-connector-python` dependency to version 2.8. This should address errors with result batching in the `fetch_r_script_checksum` method when users have a lot of scripts in their project.

Added
- Added a new optional parameter `--query-tag` to append a string to the QUERY_TAG that is attached to every SQL statement executed

Added
- Added filtering of secrets when vars are displayed on the console.
- Added filtering of secrets for deploy command when SQL statements are displayed as part of verbose output.

Changed
- Changed vars to be pretty printed to the console.
- Changed demo citibike_jinja to demonstrate secret filtering.
- Updated the Jinja templating engine section of the README.md to document Jinja autoescaping status and added warning about untrusted input.
- Updated the table of contents section of the README.md to included missing sections.

Changed
- Added `env_var` Jinja function support to migration templates.
- Backed out Jinja autoescape change from 3.3.2. The default is now to have it disabled (using autoescape=False).

Changed
- Configured Jinja to escape inputs to templates (using autoescape=True). This helps protect rendered templates against XSS and other vulnerabilities